This imposing portrait of one of the most notable courtiers of the reigns of Charles I and Charles II was painted in circa 1672, the year in which he was made Lord Chamberlain and invested with the Order of the Garter. It is the prime version having hung at Rushbroke Hall, the ancient Jermyn seat in Suffolk, for over two hundred and fifty years. Though nearing retirement, St Albans is depicted still as a commanding figure, his face reflecting his undoubted cunning and gift for self preservation.

Henry Jermyn was the son of Sir Thomas Jermyn and his wife, Catherine, daughter of Sir William Killigrew. His father had been courtier to Charles I, and Henry followed his father into public life from an early age. When still under twenty, he attended Lord Bristol's embassy to Madrid and Lord Kensington's mission to Paris regarding the marriage of Charles I to Henrietta Maria. Jermyn also entered parliament and was M.P. for Bodmin, Liverpool and Corfe Castle. His real love however was for life at Court, and in 1627 he became Gentleman Usher to Henrietta Maria. During the 1630's his increasingly close relationship to the Queen was the subject of comment and gossip, alluded to in several theatrical works. In 1641 he was a leading figure in the plan to bring down the King's army from the North in order to control parliament, but when the plot was uncovered he fled to France. He joined the Queen in the Hague, helping her to pawn the Crown jewels and raise loans, and in 1643 landed with her at Bridlington, capturing Burton-on-Trent and moving on to Oxford to join the King. He was created Baron Jermyn, and became the Queen's Lord Chamberlain and Governor of Jersey. In April 1644 he left with the Queen for France where he gathered advisors around him such as Abraham Cowley (whose Complete Works are dedicated to Jermyn) and where he worked to further the Royalist cause. He broke the news of the execution of the King to Henrietta Maria on 8th February 1649, and his intimate knowledge of the French Court was invaluable in the various efforts made to increase support for Charles II, though the new King disliked Jermyn and preferred to deal with Hyde and his circle. In December 1659 Charles made him Earl of St Albans and in 1661 he became ambassador to France where he worked to bring England and France together, a plan of which Henrietta Maria was a close supporter. From 1665 to 1667 he again served as ambassador to France, negotiating the treaty of Breda. Following Clarendon's exile, he used his influence to encourage the King to befriend Louis XIV and was influential in the eventual signing of the secret treaty of Dover in 1670.

When Henrietta Maria died at Colombe on 31st August 1669 St Albans was present, and was executor of her will. His closeness to the Queen over many years gave rise to speculation that he had married her. In her letters, Madame Baviere stated that "Charles the first's widow made a clandestine marriage with her Chevalier d'Honeur, Lord St Albans, who treated her extremely ill...". However, most commentators agree that there is no evidence of such a marriage - in the words of Miss Strickland in Queens of England "the only proof offered in the support of this assertion is that the Queen often looked pale and seemed alarmed when he entered the room".

Jermyn made substantial financial contributions to the royal cause and to repay him Charles II made him co-proprietor of the Northern Neck of Virginia and gave him valuable leases of Byfleet, Weybridge and most notably St James's Westminster. St Albans is considered to be the "founder" of London's West End. A friend of Wren, to whom he had given introductions in Paris, he commissioned from him St James's Church. He encouraged the development of St James's with wide streets (including Jermyn Street) laid out with brick houses "for the convenience of the Nobility and Gentry who were to attend upon his Majesties Person in Parliament". For over fifteen years he served as steward of Greenwich, supporting work on the Queen's House and the redevelopment of Greenwich Palace. In 1662 he brought over Le Notre from France to design the park.